In a mobile network, a network node may send a de-prioritization request to a user equipment (UE) for a current frequency or radio access technology. Such a request may be made in order to alleviate network congestion or provide for overload control.
However, while a de-prioritization request may temporarily designate the current frequency or RAT as a low priority at the UE, it may be a long time before a UE reselects to a higher priority layer even after de-prioritization.
Further, even after a public land mobile network (PLMN) change, a de-prioritized frequency or RAT may still be de-prioritized, even if that frequency is reused in the new PLMN.
In addition, if a closed subscribed group (CSG) cell is utilizing the same frequency that has been de-prioritized, the UE may not be able to connect to the CSG cell even though this would also alleviate congestion.
Further, a connected mode UE may attempt to access a de-prioritized RAT or frequency when the connection is released or after radio link failure. Further, network conditions may change rapidly and de-prioritization may not be necessary for the previously signalled duration.